Why? Cleaned with glass cleaner it looks as good as new. I suggest you stop cleaning yours with a brillo pad
If the sun gets bright and you need a tinted visor, just reach up your left hand and slide down the switch on the top left of the helmet. The tinted portion slides down from inside the helmet - simples. If it gets dark or dull, just slide it back up. No legal worries. If your helmet lacks this facility, consider buying one which has it.
Mine has. Not a fan because when mixing the two visors, it seems to get a bit misty. I end up having to just have the inner down, or just the outer.
The law is (from uk govt.direct publication): visors must have ECE, CE or BSI approval mark. During daylight hours a tint of up to 50% is permiited - legal tinted visors will be marked “For daylight use only”. I wear ESS ICE ballistic 'sunglasses) with interchangeable eyeshields (Black; Orange of Clear) under a clear visor which is always open a bit.
I did try one of those lids that have a drop down visor and almost all seem would not meet the requirement of a full time visor in it's tint if you get my drift. I couldn't get on with them anyway as I can't use contacts and need glasses for distance vision which often put them so close to the drop down visor I got condensation.
I use a tinted visor and carry a clear one with me in a visor pouch. Changing them over with Arai's visor system can be a challenge though. I've only tried a Schuberth that had one of these integral slide down visors and hated it. My experience was whenever I moved my eye line a little I had one half of my vision tinted and the other half not. I found it hugely distracting and very annoying. The integral sunshield may work for some but it's no panacea I occasionally use sunglasses with a clear visor when light conditions are changing and a decent set of sunglasses have tighter filtration so can be used in lower light conditions than a tinted visor. That said its also another layer of plastic between your eye and the road. Overall though I still find a tinted visor works best for me in bright conditions It's all a matter of personal preference